Marin's Reservoir Expansion Sparks Local Outcry

A Growing Concern Over Reservoir Expansion in Nicasio

In 2001, Monica and Michael Seybold purchased a home in Nicasio, a small community nestled near the edge of a picturesque reservoir. The location offered a peaceful lifestyle, but over time, a growing problem became evident: each winter, heavy rainfall caused flooding in the creek that ran through their backyard, eventually flowing toward the reservoir. As sediment built up, the creek bed and water levels rose, creating an increasing risk for residents.

Monica recalls one particularly severe winter storm when the flooding was so extreme that their goats were trapped, forcing her husband to swim each one back to safety. The Seybolds are not alone in their concerns; many neighbors share similar fears about the potential consequences of a proposed expansion of the Nicasio Reservoir.

The Marin Municipal Water District, which serves over 191,000 people in central and southern Marin, is under pressure to find more water sources. During the 2020-2021 drought, the district faced a critical shortage, with only a few months’ worth of water supply. In response, the district evaluated expanding the Nicasio Reservoir, which currently holds 22,340 acre-feet of water—making it the second-largest reservoir in the district.

The proposed plan involves installing a 280-foot-long, 4.4-foot-high inflatable rubber gate across the spillway crest of Seeger Dam, which was constructed in 1960. This would increase the reservoir's capacity by about 3,700 acre-feet, or 16.5%. While the initial cost for the gate is estimated at $15-$20 million, additional expenses could arise from regulatory studies and permits.

However, the expansion has sparked significant concern among local residents. Maps show that the expanded reservoir could encroach on the town’s two creeks, which are typically dry outside of the rainy season. Residents worry that during winter, the increased water levels could lead to more frequent and severe flooding, impacting homes, roads, and even the town’s only school.

Barbara Snekkevik, the principal of the Nicasio School, expressed concerns about the potential impact on the campus. During the rainy season, a culvert on the school grounds often backs up, creating standing water. The expansion plans suggest that parts of this culvert could be submerged, raising safety concerns for students.

The school’s playground, located near the confluence of Halleck and Nicasio creeks, has also experienced bank erosion due to flooding. Additionally, residents who rely on wells rather than the water district’s supply are worried about the safety of their wells and septic systems if the water levels rise.

Community members have voiced their opposition to the project, with several attending public meetings to express their concerns. Kasey Briare, a neighbor of the Seybolds, described the ongoing issues with flooding and the fear that the reservoir expansion could lead to further damage to their homes.

The water district recently extended the public comment period for the environmental impact report, allowing more time for community input. Matthew Samson, the district’s president, emphasized the importance of understanding the full scope of the project’s impact on the community.

This is not the first time the water district has considered expanding the Nicasio Reservoir. In the 1980s, a similar proposal was abandoned due to concerns about flooding and the potential need to purchase four homes. Other alternatives, such as expanding the Soulajule Reservoir or raising Kent Lake, have also faced challenges.

Currently, the district is exploring a pipeline design to draw more water from the Russian River, which supplies 25% of its current needs. However, questions remain about the financial feasibility of the Nicasio expansion, including the potential costs of property condemnation.

As the public comment period continues, residents like Michael Seybold are left wondering about the future of their homes. For many, the idea of selling their properties seems impossible, given the risks associated with the proposed expansion.

The debate over the Nicasio Reservoir expansion highlights the complex balance between meeting growing water demands and protecting the interests of local communities. As the process moves forward, the voices of those affected will continue to play a crucial role in shaping the final decision.